108 PHYSIOGRAPHY. 



Calcareous Spar. 



compact limestone ; the former of granular limestone. The simple vari- 

 eties occur in drusy cavities, more frequently in veins than in beds, ac- 

 companied with the varieties of different species. Columnar composi- 

 tions have been observed to form veins by themselves, and a great num- 

 ber of varieties are met with in the cavities of several rocks. Slate spar 

 is generally a product of beds of granular limestone; calcareous tufa 

 and rock-milk, being of a sintery formation, occur upon the surface, and 

 in fissures of limestone rocks, and rock-rnilk in particular is generally a 

 very pure carbonate of lime. Stalactitic and pisiform varieties are pro- 

 duced by calcareous springs and other waters. The original repository 

 of Anthracolite is not known, it having as yet been found only in large 

 boulders. The impure varieties occur in particular strata, between those 

 ef compound varieties of other species. This species is very common in 

 petrifactions, imbedded in compact varieties of the same species. 



4. Calcareous Spar is one of the most widely diffused species. Seve- 

 ral of its varieties have a considerable share in the constitution of moun- 

 tains in many countries. This is particularly true in Switzerland, Italy, 

 Carniola, Carinthia, Salzburg, Stiria, and in several parts of the United 

 States. Beds of granular limestone in gneiss and mica slate, abound in 

 all the New England States ; also in New York, New Jersey and Penn- 

 sylvania ; also, of the compact limestone, in Upper and Lo*ver Canada, 

 upon Lake Chanoplain, and throughout the vast district contained be- 

 tween the Alleghany mountains, the lakes and the Mississippi. Of crys- 

 tallized varieties, the most remarkable occur in Derbyshire and Cum- 

 berland, in the mining districts of Saxony and Bohemia, in the Hartz, in 

 Carinthia, Stiria, Hungary, and France; and in North America, at By- 

 town, (Lower Canada,) Kingston, (Upper Canada,) Lockport and Ley- 

 den, (New York,) and the Silver mines of Mexico. Iceland is the lo- 

 cality of its finest and most transparent varieties, from whence come the 

 best pieces of the doubly refracting spar. The crystallized sandstone of 

 Fontainbleau in France, (Chaux carbonatde quartzifere O/*HAUY,) is a 

 variety of calcareous spar, mechanically mixed with sand. When crys- 

 tallized, it assumes the form of the inverted rhomboid. Argentine 

 occurs in Saxony, Norway and Cornwall, and in the United States 

 at Williamsburg and Southampton, (Mass.,) in the lead veins, as well as 

 in the iron mine of Franconia, (N. H.) Picrolite is found in Carniola, 

 and at Carlsbad in Bohemia. Anthracolite is found in Salzburg. Calca- 

 reous Tufa abounds in the States of New York and Ohio, where its for- 

 mation at the surface of the ground, or in cavities of compact limestone, 

 is constantly progressing. Stalactitic varieties are particularly abundant 



